Proportioning pump



Dec. 25, 1945. W,J HUGHES 2,391,703

' PROPORTIONING PUMP Filed March e, 1943 2 Sheets-Shet. 1

IN VEN TOR.

1945- w. J. HUGHVES Filed March 6, 1943 PROPORTIONING PUMP 2 Sheets- Sheet 2 I JULY 0N INVENTOR.

Patented Dec. 25, 1945 UNITED STATES PATENT orrlcs PROPORTIONING PUMP Walter .1. Hughes, Chicago, 111., assignor to Infilco Incorporated, Chicago, 111., a corporation of Delaware Application March 6, 1943, Serial No. 478,191

10 Claims.

' and tear and mechanical as well as other difliculties.

A principal object of the invention is to provide a chemical proportioning pump which will select a predetermined amount of a chemical solution from a solution tank open to atmospheric pressure and transfer it to a zone of liquid under pressure, utilizing'for this purpose energy derived from the liquid under pressure.

All pumps with which I am familiar have power applied to the pumping element and control the suction and discharge of pumped ,material through check valves which are operated by the direction of pressure from the pumping element, and which therefore act only after the pumping element has begun movement in one direction or the other. A chemical proportioning pump customarily is used to supply very small dosages with each stroke, such as from A cubic centimeter to 8 or 10 cubic centimeters, so that any slippage of pumped material around the check valve between the beginning of movement of the pumping element and the complete closure of the appropriate check valve becomes proportionately large and therefore quite important.

In the device of the present invention the valve action is first mechanically perfect and is independent of pressure difierences on the two sides of the valve, and the action of the pumping element follows the valve action so that there can be no slippage of pumped material by the check valve.

Another principal object of this invention therefore is to provide a pump having a sequence of operations for. filling and discharging which is actuated by alternating valve action in such manner that slippage is substantially'completely eliminated, so that even though its displacement is adjustable and exceedingly small, the amount of liquid pumped is accurately controlled.

Another object of the invention is the provision of a chemical proportioning pump which utilizes mechanically actuated valves operable in timed sequence to control the forcing action of the chemical from an open solution tank into a pressure zone, the pump deriving its operating force from liquid under pressure in the pressure zone. A further object of the invention is the provision of such a pump which incorporates two diaphragms of different effective areas which form within the pump a pumping chamber in one section and a, forcing chamber in another section,

and also forming an intermediate constant pressure chamber between the two, the diaphragms being connected to reciprocate as a unit responsive to liquid flowing in a pressure zone to which a chemical solution is to be injected.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combination of elements,

and arrangement of parts, which will be exemplifled in the construction hereinafter set forth and the scope of the application of which will be indicated in the claims.

For a, fuller understanding of the nature and objects of the invention reference should be had to the following detailed description taken in conneetion with the accompanying drawings, in which:

Fig. 1 is a transverse view partly in section and with parts broken away, diagrammatically illustrating an arrangement of parts constituting a Referring more particularly to Fig. 1 of the.

drawings, there is indicated'generally at ll! a pumping block housing made of some suitable material such as hard rubber or the like. This housing preferably comprises three sections it, l2 and I3 which suitably can be dismantled and bolted together. Within the housing are located two diaphragms l4 and 15, respectively, preferably composed of rubber. The disphragm M is marginally secured between sections II and 12 of the housing block and the marginal portions of the diaphragm l5 are similarly secured between the sections 12 and I3. Centrally of the diaphragms l4 and I5 are bosses l6 and I1, and,

I8 and 19, respectively, on opposite sides of each diaphragm. The diaphragms l4 and 15 through the bosses l1 and 18 are connected together by a link 20. These two spaced apart diaphragms consequently separate the housing into three distinct chambers, namely, a forcing ,or engine chamber 2!, an intermediate chamber 22, and a pumping chamber 23. Within the engine'chamher 2| is a proportioning adjusting screw 24 around which is mounted a spring which is seated at one end against the head of the housing and at its other end against the boss f6. The pumping chamber preferably has located opposite the boss IS, on the diaphragm IS, a projection 28 adapted definitely to limit the extent of the discharge travel or discharge distention of the diaphragm 5.

In cooperative associated with the aforementioned three chambers, and in any suitable arrangement within the block housing H) are a series of valves indicated generally at 21. There are four of these valves and for convenience in illustration bear the legends I, to represent the first or suction valve; II, the second or discharge valve; III, the third or waste valve; and IV, the pressure valve. operate in this order but in grouped, timed sequence as will more fully appear hereinafter.

No. I valve is connected by a line 28 to a solution tank 29. This valve is also connected to the pumping chamber 23 by a line 30. No. II valve is connected to line 30 by a line 3|. This second valve is also connected by a line 33 to a main 32 having liquid under pressure, the main 32 hereinafter being referred to as a pressure zone. No. III valve is connected by a line 34 to the engine, or forcing, chamber 2|. Also, valve No. III has a line 35 discharging waste liquid to atmosphere. A branch line 33 leads from line 34 to No. IV valve. This last valve, No. IV, is directly connected by a line 31 to the main line or pressure zone 32. In addition, a branch line 38 leads from line 31 to the constant pressure or intermediate chamber 22.

The control of the valves 1, II, III and IV preferably is effected mechanically. To this end there is utilized in direct association with each valve 9. motor-driven cam shaft, the R. P. M. of which is regulated by a motor-reducer 10, geared to rotate at any desired speed, either fixed or adjustable, to give a desired number of pump displacements per unit of time, all of which i schematically illustrated generally at 39. The cam shaft 40 has mounted thereon cams 4|, 42, 43 and 44 which control the operation of valves I to IV respectively through cam follower yokes 45. 46, 41 and 48 linked to valve stems 49, 50, 5| and 52 respectively. The cams 4| to 44 are alternately directed away from each other in the same plane. That is, cams 4| and 43 are in identical positions while cams 42 and 44 are also in other identical-positions directly opposite that of cams 4| and 43.

A detailed analysis of a preferred form of valve and cam arrangement may best be obtained by referring to Figs. 2 to 4. A plug 53 of flexible material such as, for example, rubber is molded around a valve stem. Integral with the plug is a diaphragm 54. Mounted around the valve stem and against a shoulder extension of the plug centrally of the diaphragm is a spring 55. The diaphragm is marginally secured between a valve block 56 and-a valve spring cage 51, each of which is secured together with the marginal portion of the diaphragm between them by suitable machine screws. The valve block has entrance and exit ports 58 and 59 respectively, either of which may be connected to a pressure line. The bottom of the plug 53 will be seated against the entrance of the port 58 and likewise removed therefrom by the reciprocation of the valve stem responsive to These valves, however, do not phragm is particularly suitable for use in chemical pumps. Any chemical entering the valve chamber 62 is completely out of contact with metal since the valve block, the plug and the diaphragm are all of non-metallic materials. The valve mechanism is packless or glandless and provides an hermetic resilient seal at the plug seat as well as around the diaphragm. The valve is also positively seated by the action of the spring.

A preferred arrangement of parts for securing a desirable cam and valve action is illustrated in Fig. 4. As above indicated it is essential that cams 4| and 43 operate in unison and immediately upon the performance of their cycle of operation, it is essential that cams 42 and 44 similarly perform their cycle of .operation. Therefore, a cam shaft having oppositely directed cams as hereinbefore described will operate rocker arms in timed sequence which alternately will institute the functioning of valves I (suction) and III (waste) and thereafter valves II (discharge) and IV (pressure).

The diaphragms l4 and I5 within the housing iii (Fig. 1) are essentially of different effective areas in order to insure the successful operation of the device. In the instant illustration it will be seen that the effective area of the pumping diaphragm I5 is smaller than the effective area of the forcing diaphragm I4. The relation between these-effective areas may be increased -or decreased as desired. It will become apparent that the larger of the diaphragms should be associated with the forcing or engine chamber whereas the smaller should always be associated with the pumping chamber. with this difference in effective area the simultaneous opening of the No. I (suction) and No. in (waste) valves will provide a net suction force within the pumping chamber 23 which is only opposed by the function of the spring 25. This net suction force re-- sults from the fact that, due to the closing of valves II (discharge) and IV (pressure), engine chamber 2| and pumping chamber 23 are essentially open to the atmosphere, and liquid under pressure enters the intermediate chamber 22 only. In the intermediate chamber 22 the larger effective area of the diaphragm l4 causes the total force to the left to overbalance the total force to the right by an amount at least sufficient to depress the spring 25 and move both diaphragms to the left. The simultaneous deflection of the pumping diaphragm l5 together wtih the forcing diaphragm I4 away from the pumping chamber 23 enlarges the size of the latter to suck in a selected amount of chemical when the forcing chamber 23 is partially exhausted and thrown out of balance. When the balance on each side of the two diaphragms is restored by the closing of valves I (suction) and III (waste) and the opening of valves II (discharge) and IV (pressure) so that all three chambers are connected to high pressure zone 32, the chemical is pumped out of the pumping chamber by a net forcing power which is solely equivalent to the energy stored within the spring 25. The foregoing functions will even more readily become apparent with a description of the operation of the entire apparatus.

The suction stroke of pump and forcing diaphragms When the motor-reducer 10 rotates the cam shaft 40 to turn the cams 4| and 43 to the positions indicated in Fig. 1 of the drawings, valve I will open to allow solution to pass from the soluchamber 23. Simultaneously therewith valve 111 has opened and permits discharge from chamber 2| of a portion of its contents through the line 34, through the valve III and out of line 35 as waste to atmosphere. This discharge is forceful from the line pressure in the intermediate chamber upon opening line 34 to atmosphere due to the fact that the net pressure on the diaphragm I4 is to the left and, in view of it being larger than diaphragm IS, the total force to the left is greater than the total force to the right. As a result, the intermediate, or constant pressure, chamber 22 is thrown out of balance and the forcing diaphragm H together with the pumping diaphragm l5 moves to the left until the leftward travel is limited by the adjustable stop screw 24 and a charge of solution is sucked into the pumping chamber 23. The suction operation is initiated by the opening of valves I and III, and is completed with their closing, which occurs when the cams 4| and t3 have rotated through an angle'of less than 180 but great enough to efiect complete opening and closing of their associated valves I and III. Simultaneously the spring 25 has been compressed by the leftward travel of the diaphragms.

The discharge three chambers permits the spring 25 to fully and completely force the measured amount of chemical into the high pressure line.

It further will be apparent that where the flow through the high pressure conduit 32 is variable, the pump herein described can readily be adapted to pump a proportional amount of chemical With the completion of the foregoing suction operation, cams 46 and 48 rotate into their effective operating angles through a supplementary rotation of 180, within which angle valves II and IV are opened and closed. While open, No. IV valve permits line pressure to enter its valve chamber through line 31 from pressure zone 32, allowing liquid from the main to pass through and out of its chamber into branch line 36, into line 34' and thence into forcing chamber 2|. This restores to balance or equilibrium the pressure on the two sides of the forcing diaphragm.

Also valve II (discharge) opened simultaneously with valve IV (pressure) connects the pressure line 32 through line 33, chamber of valve II, and line 30 to the pump chamber 23, now filled with chemical. Thus the pump diaphragm is also in balance by line pressure on the pump side and by line pressure in the intermediate chamber. The spring 25 having been compressed by the previous leftward travel during the filling or suction stroke now presents an unopposed force to the right. This force moves both diaphragms to the right and effects discharge of the chemical from pump chamber to high pressure line 32 through valve II and connections 33 and 33. The rightward movement ceases when boss i9 comes against the stop 26, in which position the diaphragm remain until the next suction or leftward stroke is effected by opening of valves I and III.

It will be observed that the capacity of the pump for each reciprocation is governed by the position of the adjustable stop screw 24. It is thus possible to pump small dosages accurately and over an extremely large range of volumes.

It will also be evident that the motor required for the pump of the present invention need develop only sufficient power to turn the cam shaft d5). In contrast, pumps of the prior art have rethereinto. In such an installation the conduit 32 could be provided with a meter H, designed to give a predetermined impulse upon the passage of a desired amount of liquid to the motor-reducer 10 through a suitable power connection l2.' In that event, the motor would be so wired that upon the giving of such an impulse, from the meter H, the motor would run for a period sufficient to complete one revolution of the cam shaft 40. Thus upon the passage of a predetermined amount of liquid through the conduit 32 the motor would be operated to make one complete turn of the cam shaft 42, thereby making one complete stroke of the pump and introducing one unit of dosin reagent.

It will thus be seen that the objects hereinbefore set forth can readily and efficiently be attained, and since certain changes may be made in the above construction and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following 'claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scop of the I invention which, as a matter of language, might be said to fall therebetween. Having described my invention, what I claim as new and desire to secure by LettersPatent, is:

4 1. A chemical pump, which comprises in combination, a housing, spaced apart diaphragms partitioning said housing into a forcing chamber, a constant pressure chamber and a pumping chamber adjacent each other, a conduit connected to the said constant pressure and forcing chambers and adapted to connect the same to a source of liquid under pressure, and mechanically actuated valves associated with said pumping and forcing chambers and cooperating to alternately connect said forcing chamber to atmosphere and to admit liquid under pressure thereto, and in unison therewith to admit liquid to be pumped to said pumping chamber and discharge it therefrom.

2. In a pump the combination of a housing, cooperatively associated, spaced apart diaphragms partitioning said housing into a pumping chamber, an intermediate chamber and a iorcing chamber, and means to reciprocate saidediaphragims, said means comprising means to maintain a constant pressure in said intermediate chamber, means operative to vary the pressure in said forcing chamber from equal to said constant pressure in said intermediate chamber to less than that pressure, and to restore the pressure in said forcing chamber to equal with said pressure in said intermediate chamber, the effectiv area of i.

pumped into said pumping chamber simultaneously with each movement of the diaphragms in suction direction and for allowingdischarge of pumped liquid therefrom simultaneously with each movement of said diaphragm in discharge direction.

3. .A pumping apparatus comprising a housing, a pair of spaced apart diaphragms in said housing separating in lateral sequence therein a forcing chamber, an equalizing chamber, and a pumping chamber, a constantly open inlet for pressure liqquid opening into said equalizing chamber, mechanically actuated means for alternatingly admitting liquid to be pumped to said pumping chamber and permit discharge of such admitted liquid therefrom, and in unison therewith to alterna'tingly connect said forcing chamber to atmosphere and to admit liquid under pressure thereto, and a member bearing against one of said diaphragms and operable to move said diaphragms in a discharge direction when said forcing chamber receives liquid under pressure, said diaphragms being of such effective areas and so arranged that upon connecting of said forcing chamber to atmosphere they will be moved in a suction direction.

4. An hydraulic pumping apparatus comprising a housing, a pair of spaced apart diaphragms in said housing separating a pumping chamber between the first of said diaphragms and a wall of said housing, a constant pressure chamber between said diaphragms and a forcing chamber between the second of said diaphragms and another wall of said housing, said second diaphragm being of larger effective area than said first diaphragm, a pressure member in said forcing chamber bearing against said larger diaphragm, an inlet into said constant pressure chamber adapted to be connected to a zone of pressure liquid, a first conduit adapted to admit liquid to be pumped to said pumping chamber, asecond conduit adapted to permit discharge of liquid to be pumped from said pumping chamber, a third conduit adapted to connect said forcing chamber to atmosphere, a fourth conduit adapted to admit pressure liquid to said forcing chamber, and independently actuated valve means associated with said conduits and so constructed and arranged as to'open the first and third conduits and close the second and fourth conduits an alternately to close the first and third conduits and open the second and fourth conduits.

5. A pump comprising a housing, flexible diaphragms in said housing dividing the same into a forcing chamber, a pumping chamber and an intermediate constant pressure chamber, the dia- 'phragm adjacent the forcing chamber having a larger effective area than the diaphragm adjacent the pumpin chamber, a link connecting said diaphragms, conduits opening into said forcing and pumping chambers and adapted to connect the same to liquid pressure equal to that prevailing in the constant pressure chamber, a waste conduit from said forcing chamber, a suction conduit connected to said pumping chamber, valves in said conduits, a pressure member in said forcing chamber bearing against one of said diaphragms, and actuating means operable to simultaneously open the valves in said waste conduit and said suction conduit, and close the other two valves and then close said first mentioned valves and open the other two.

6. The apparatus of'claim 5 wherein the actuating means for said first and second valves are so constructed and arranged as to start opening of one pair of valves only after closing of the other pair has been completed.

7. The apparatus of claim 5 wherein each of said valves comprises a valve housing having an entrance and an exit port, a valve stem mounted in said housing for reciprocal movement to and away from one of said ports, a valve plug. molded around said stem, and a diaphragm integral with said plug, the peripheral edge of said diaphragm being fastened to said valve housing.

8. The apparatus of claim 3 comprising also an adjustable stop member limiting movement of said diaphragms.

9. A pump comprising a housing, a pair of laterally spaced rigidly connected diaphragms forming in said housing a pumping. chamber, an intermediate chamber and a forcing chamber, the diaphragm between said forcing chamber and said intermediate chamber being of greater eilective area than the diaphragm between the intermediate chamber and th pumping chamber, an

inlet for pressure liquid into said intermediate chamber, a pressure member bearing against one of said dlaphragms and so arranged as to force the diaphragms toward the pumping chamber, an inlet for liquid to be pumped into said pumping chamber, a suction control valve for said inlet. an outlet from said pumping chamber for liquid to be pumped, a discharge control valve for said outlet, a waste outlet from said forcing chamber, a waste control valve for said waste outlet, an inlet for pressure liquid into said forcing chamber, a pressure control valve for said inlet, and actuating means for said valves so constructed and arranged as to open said suction control valve and said waste control valve and close said discharge control valve and said pressure control valve, and alternatingly therewith open said discharge control valve and said pressure control valve and close said suction control valve and said waste valve.

10. A chemical pump comprising a housing, a pair of laterally spaced diaphragms in said housing and forming therein a pumping chamber, an intermediate chamber and a forcing chamber, the forcing chamber diaphragm being of larger effective area than the pumping chamber diaphragm, spacing means rigidly connecting said diaphragms, a spring in said forcing chamber and bearing against said forcing chamber diaphragm, an adjustable stop member projecting into said forcing chamber, an inlet into said intermediate chamber, four valve chambers in said housing, each of said valve chambers having two ports, a valve mounted in each of said valve chambers and adapted upon operation thereof to open and close one of said'ports, two of said valve chambers having one of their ports connected to said pumping chamber, the other two valve chambers having one of their ports connected to said forcing chamber, the second ports of said first group of valves being a suction port and a discharge port respectively for liquid to be pumped into and from said pumping chamber, the second ports of said second group of valves being a waste port and a pressure port respectively for fiow of pressure liquid into and from said forcing chamber,

and actuating means independently operable to actuate said valves to open and close said suction and waste ports in unison and said discharge and pressure ports in unison and to complete each opening and closing cycle in a predetermined period of time.

- WALTER J. HUGHES. 

